UNITED STATES GEOLOGICAL SURVEY

TEI-143 (

A SEMIQUANTITATIVE SPECTROGRAPHIC METHOD FOR THE ANALYSIS OF MINERALS, ROCKS, AND ORES

ByC. L. WaringC. S. Annell

This preliminary report is released without editorial and technical review for conformity with official standards and nomenclature, to make the information available to interested organizations and to stimulate the search for uranium deposits.

February 1951

Prepared by the Geological Survey for the UNITED STATES ATOMIC ENERGY COMMISSION Technical Information Service, Oak Ridge, Tennessee

i WJ41**LotS.J'w

JAN 1 0 2001

CHEMISTBT

In an effort to save you and your government time and money, this report has been reproduced direct from copy as submitted to the Technical Information Service.

AEG, Oak Ridge, Tenn.-W23708

A SMIQUAKTITATIVE SPBCTEOGBAPHIC METHOD FOE

TEE: ANALYSIS OF MOTTR&LS, ROCKS, AM) ORES

C. Ii. Waring and C. S. Anne 11

ABSTRACT

Th^

INTRODUCTION

The spectrographic laboratories of the Geological Survey

receive for analysis each year a very large number of samples of

radioactive minerals, rocks and ores in connection with the

investigation of radioactive raw materials, a program in which

the Survey is engaged for the Atomic Energy Commission,, It is

desirable to know the trace-elements content of this material and

for many purposes it is necessary to gain some knowledge of the

amounts of major constituents present without going to the trouble

of making chemical analyses.

The quantity and complex nature of the samples received have

emphasized the need for a spectrographic method to determine a

maximum number of elements in a limited time with a reasonable

degree of accuracy. In spectrographic parlance such a method is

termed "semiquantitative" and the results are usually reported in

orders of magnitude of weight percentages of the elements (not the

oxides).

A survey of the literature I/ reveals that several slightly

similar methods are being applied in other laboratories on materials

of a different nature * As a starting point, it was decided to use

powdered samples in order to eliminate costly dissolution techniques

As it was not intended to provide complete quantitative data, the

I/ Meggers, W. F», Emission spectroscopyg Anal. Chemistry, vol. 22, no. 1, pp ft 18-23, 1950.

internal-standard, buffer, and carrier-distillation methods were

not considered, nor could any definite advantage "be anticipated

in employing the cathode-layer method with Its critical optical

alinement. .Ahrens £/ compared the cathode-layer and anode-exci-

tation methods and found them approximately equally sensitive.

An investigation of the various excitation sources indicates

that the direct current arc gives' the best sensitivity or produces

a higher degree of sample excitation so that lines emitted by

elements in low concentrations may be recorded. The interrupted

direct-current arc supplied by the Multisource produces a similar

degree of sensitivity -with the added advantage of simple operation.

The nature of the interrupted arc would lead one to expect better

control and attack of sample. It was hoped that this source would

contribute to the reduction of interference of other elements or

matrix effects,

Owing to these advantages the Moltisource was selected to

excite the graphite-mixed samples, which had been placed in the

crater of a graphite electrode at the positive side of the arc.

The purpose of the graphite addition was to prevent the formation

of mobile beads of molten salts, oxides, or metals, to assist in

the volatilization of elements of high boiling points or of elements

existing in extremely nonvolatile compounds, and to steady the arc

.2/ Ahrens, L. H., Qualitative spectrochemical analysis of minerals and rocks; Gepl, Soc. South Africa Trans. %?, pp.

with a minimum of spraying or mechanical loss of sample.

In the present state of development of spectrochemistry an

exact solution is precluded. This paper presents a practical solu-

tion that is being studied as it is applied to a wide variety of

materials, with the hope that the method either will prove to be

sound or will give basic data leading to a more exact solution.

Acknowledgments

The authors wish to express appreciation to their associates

of the U* S. Geological Survey, expecially to A. W. Helz for his

technical assistance and valuable suggestions, Helen Worthing for

her aid in the standardization work and for performing part of the

analyses, and to Jane Titcomb who reviewed and edited the manuscript.

OUTLUE OF METHODy

The guide followed in working out the method and organizing

this paper was an unpublished tentative outline for a suggested

method of emission spectrochemical analysis, issued about 19^8

by Committee E-2 on Spectrographic Analysis, American Society for

Testing Materials *

A method is provided for determining 55 elements in one ex-

posure. Table 1 shows the minimum concentration of the elements

detectable by the method Better sensitivity for many of these

elements may be obtained by special methods.

I

Table 1, Threshold or visual detection limits of the 55 elements included in the semiquantitative spectrographic method

Based on 10 Big of sample

Element

AsAlAgBBa

BeBiCeCoCb

Cd .CuCaOrCs

By 'ErFeGaGe

GdHfHgInK

LaLi

I/listed.

Minimum cone, detectable (in percent)

0.10,00010,0010 0Q010.001

0.0010,001Ocl

0,0010,01

0,010.00010.00010.0011.0

0.010.010,0010.010.001

0.010.10.10,001

(0,0001) I/ 0.1s

0.01(0.0001 )!/ 0.1

-

Element

MoMgMnNa (O.OOOl)l/Ni

IdPFtPbPr

RbReSbSrSn

SmSiScThTl

TiTaUV¥

YZrZn

A second exposure is necessary to produce the

Minimum cone, detectable (in percent)

0.0010.00010,0010.10.001

0,010.10,010.010.01

10.00.010.0010*010.01

0,10.00010.10.10,1

0.001Ocl

0.10.010.1

0.0010-0010,001

high sensitivity

The method is applicable when samples must "be inspected

previous to quantitative spectrographic or chemical analysis.

For many purposes the semiquantitative results are sufficient,

and eliminate the expense of quantitative tests. The selection

of a few samples from a large quantity of materials for more

accurate tests is one of the most important applications of the

semiquantitative spectrographic method. All of the elements listed

in table 1 may be checked in one exposure, except the alkalies, Li,

Ka, and K, at concentrations of lofts t&aH'O.l p®rcen1& which require

a second exposure in the red region of the spectrum (5500-8000 A).

The method has been applied to the analysis of the following:

phosphate rocks, clays, sandstones, limestones, slags, coal ash,

sulfur ore, sphene, allanite, apatite, zircon, microlite, galena,

idocrase, caraotite, hewettite, sphalerite, thorite, vanoxite,

uranothorite, brannerite, davidite, bastnaesite, miscellaneous

precipitates, tap- and mine-water residues, leach products, and

other types of materials

7

decreasing from 10 to 10" , In preparing the standard plates, an

inorganic-solution technique is employed. Standard solutions are

prepared from the purest chemicals obtainable, These solutions

are added to the electrode cups^ and evaporated before arcing*

Apparatus

Excitation source - Applied Research Laboratories, Multisource interrupted direct-current arc*

Spectrograph - Jarrell-Ash 21-foot, Wadsworth-mounted grating.

Intensity control - Applied Research Laboratories neutral filters.

Viewing box - Jarrell-Ash.

Developing equipment - Applied Research Laboratories rocking developing tank, plate washer, and drier ,

Electrode cuttersA - Lower electrodes, designed to cut 1/^-inch electrodes

(outside diameter 0,22 inch, inside diameter .0*19 inch, depth of crater 0.12 inch, depth of shoulder 0,12 inch)*

B - Upper electrodes, hemispherical 0

8

A O-.l-ml aliquot is added to the sealed 5/ electrode cups from

a micropipette and permitted to dry on an asbestos-covered hot

plate (temperature approximately 100°C.)c A few milligrams of

pure graphite are added to the remaining salts in the electrodes.

The electrodes are arced for 60 seconds. The following Multisource

conditions and plate-processing conditions are used:

Capacitance

Inductance

Resistance

Initiator

Phase

Strike

Amperes

Spectrograph

Distance from electrode to slit

Slit

Optics

Emulsion

Development

Gap

Transmission

60 microfarads

ll-OO microhenries

15 ohms

high

0

strike position

12

Jarrell-Ash

53-5 cm

25 microns

arc image focused on grating

1-L (Eastman)

k minutes at l8°C, + 1/2°C., D-19

5-6 mm

6k percent

3/ Seal is made of 1 percent parafin + "benzine solution.

Analysis of unknowns

A 10-mg sample is weighed, mixed thoroughly with two parts of

pure graphite in the weighing pan, and placed in the electrode cup

through a small glass funnel drawn from pyrex tubing. The unknowns

are arced for a period of 60 seconds* Spectra of iron k/ and also

of an aluminum alloy are recorded on each plate, along with the

spectra of the unknowns. Reference points for locating lines and

a general index of exposure, plate sensitivity, and development

thus are obtained. The aluminum alloy of known composition also

serves as a standard^ when arced for 120 seconds at 32-percent trans-

mission, with no change in the other conditions. The above conditions

for recording the aluminum spectra were determined experimentally.

After the plates are processed, the quantities of unknown elements

are estimated by visual comparison of certain lines of the elements

in question (table 2) with those on standard plates. The results

are reported in the following brackets; over 10.0 percent, 1 80-1Q.O

percent, 0,1-1.0 percent, 0,01-0.1 percent, 0.001-0,01 percent, and

0,0001-0,001 percent. Work has been planned to include a lower per-

centage bracket (0.00001-0*0001 percent), as a few of the elements

are detectable in concentrations of less than 0.0001 percent.

j4/ Lower electrode is 1/4-inch iron rod, upper electrode is carbon (0.06-inch hemispherical radius). Arcing time 60 seconds, 4~5 amperes, 300 volts, transmission 6k percent.

10

Table 2 a-Wire lines used in the semiq-oantitative method

Element

Aa

Al

Ag

B

Ba

Be

Bi

Ce

Go

*r

Wavelengths Element (in A)

2780*2 Cb2349.842288012

3092 07 Gd3082.23059.92660»42652*52575ol Oa25680 0

3382n93280.7

2497.8 Ca2496.7

5535^554554oQ43071*6 Cr

3321.32348^6

3067a72897o9

Cs4222.64186*64Q400 74012^4

93T3465*83453*53449.23405P 13283* 5 Fe3243*8

: M$.S3^;.i '

9*1882

9*6l£Z

-6*90^

og

TS

7 C, ^'X^

PS

7*^ u *j

"fH

6*5685

(TUT)

TC

12

DISCUSSION

The choice of lines to be employed for estimating concentrations

of the elements is guided by the major components of the sample and

by possible interferences. For example, when inspecting a spectro-

gram for zinc, the zinc line (3302.6 A) cannot be used if the sample

contains greater than 1.0 percent of sodium, because of sodium (3302.3 A)

interferenceo The zinc lines, 33^5.0 A and 468019.1 A, should be employed. Titanium,

32^2,0 A, in amounts more than 0.1 percent will interfere with yttrium,

32^2.3 A,

When the sample contains more than 0.1 percent chromium, the

2780.7 A chromium line has an undesirable effect on arsenic 2780.2 A.

Chromium, 2731.9 A, and arsenic, 23^9.84 A, are substituted. Cerium

lines, 4l86.6, WK).7, ^012 k A, below a 1.0-percent concentration

are masked by the cyanogen band, The cerium line, 4222.6 A, occurs

in a clearer part of the spectrum, and has a detectable limit of

0.1 percent,,

The presence of 5 percent or more of calcium fluoride has a

general enhancing effect on aluminum. The spectrum of aluminum

in concentration of about 0.01 percent then appears ten times too

intense. This effect was not observed in phosphate-rock samples,

In feldspar samples a depressing effect was observed on aluminum

to the extent that a percentage estimation of this element could

be incorrect by one bracket,-

13

Table 1 shows the threshold values or visual detection limits

of the elements included in the method. The method is not designed

for maximum sensitivity, but is applicable rather for a -general

treatment by which 55 elements may "be checked on one exposure. Ex-

perimental data, suggest that increased sensitivities can be obtained

for some elements by increasing the arcing time to 120 seconds, thus

insuring complete consumption of the sample. This conversion is

p3.armed when time becomes available to prepare the proper standard

plates,

RESULTS AHD TABLES

The method has been employed to complete 15,000-20,000 deter-

minations during a nine-month period. Of these determinations 50^

were checked by chemical methods and indicated approximately 10

disagreements^ in the magnitude of one bracket, with the spectro-

graphic results. Comparison of chemical and spectrographic analyses

are shown in tables 3-8, Some of the results were borderline cases

in the sense that there was some doubt as to which of two adjacent

brackets they belonged. This, however, is true of any procedure

which involves assigning the results to one of a series of arbitrary

categories. Because no particular element was the chief offender,

the sampling and segregation may be at fault, and not the method.

Table 3*

Com

pari

son

of c

hemical and

spec

trog

raph

ic an

alys

es of s

ampl

es of Flo

rida

phosphate r

ock

(TWS

-61,

TWC-908, Lot

52*0

Elem

ent

P Ca Fe Al Si Na K Mg Mn V Ti Cr

No.

1 chem

I/

spec

11.5

a

19.6

a

1.26

c

0.52

c

*K1

b

0.75

c

0.25

c

0.63

' b

0.02

3 d

0.00

56

d

0.03

6 d

0.00

e

Ho.

2 chem I/

spec

12.6

a

18.3

a

1.19

'

c

O.kk

c

3.9

b

0.82

c

0.28

c

0.69

b

0.023

d

0.0056

d

0.01

2 d

0.00

e

No.

3 ch

em I/

spec

12.7

a

17*7

a

0.^6

c

0.66

c

7.6

b

0.39

c

0.02

5 d

0.09

d

0.02

3 d

000056

d

0.00

6 d

0.00

e

Ho.

k ch

em I/

spec

15.8

a

19. b

a

0.87

c

0.33

c

*KO

b

0.22

c

0.033

cL

0.16

c

0.03

1 d

0.01

1 d

0.01

8 d

0.00

e

No.

5 ch

em I/

spec

15.5

a

19.8

a

Io25

c

0,07

c

2.9

b

0.16

c

OaOl6

d

O.I

1}- c

0.10

8 d

0.01^

d

0.03

6 d

0.00

e

a =

10.+

, b

= 1.0-10.0,

c »

0.1-1.0,

d

= 0.

01-0

.1,

e = 0.

001-

0.01

I/ Chemical

res

ults

=

oxid

es redu

ced to

el

emen

ts

Table 4. Comparison of chemical an

d spectrographic an

alys

es of s

ampl

es of Flo

rida

phosphate rock

(TWS

-86,

TWC-780, Lo

t 2-2J)

Elem

ent

Si P Al Zr Ca Fe Mn Mg Na Ti Cr V

BP-1

chem

I/

spec

25.4

a

4.8

b

9.5

a

0.08

c

0.68

c

1,8

b

0,00

e

0.18

c

0.21

c

0.44

c

0.03

d

0.01

e

BP-2

chem I/

spec

18,6

a

5.7

b

12.8

a

0.08

c

0,64

c

2.0

b

0.00

e

0.23

c

0.30

d

0.69

c

0.11

d

0.01

e

BP-3

chem I/

spec

23.8

a

5.1

b

10.7

a

0.1

c

0.05

d

1.7

b

0.00

e

0.29

c

0.25

d

0.50

c

0.13

d

0.00

e

BP-5

chem I/

spec

28.8

a

3.1

b

8.8

a

0.1

c

0.08

d

1.5

b

0.01

e

0.17

c

0.04

5 e

0.40

c

0,06

d

0.01

e

BP-6

chem I/ s

pec

36.8

a

1.1

b

5.3

a

0,09

c

0.29

c

1.2

b

0.00

e

0.15

c

0.13

d

0.24

c

0.06

d

0.00

e

BP-7

chem I/

spec

38.2

a

1.4

b

4.2

a

0.1

c

0.16

d

1,7

b

0.01

e

0.12

c

0.19

d

0.21

c

0.03

d

0.00

e

HP-8

chem

I/

spec

38.8

a

1.5

b

3.6

a

0.1

c

0.05

d

1.5

b

0,01

e

0,13

c

0.12

d

0.20

c

0.04

d

0.00

e

a =

10,+

, b

= 1.

0-10

,0,

c =

0.1-

1.0,

d

= 0.01-0.1,

e =

0.00

1-0.

1

Chem

ical

res

ults

=

oxides reduced

to el

emen

ts

Tabl

e 5« Comparison

of chemical and s

pect

rogr

aphi

c analyses of red and gray

clay

sfr

om the Co

lorado P

late

au

(TWS-118,

Lot

0-20)

Elem

ent

Ca Si Fe Al Mg Cu Na K Ti V

Bed

chem

I/

1.7

28.0

3.84

5.6

2.46

1.37

0.03

5.0

0.35

0.04

clay

spec

1.0-

10.0

10*+

1.0-10.0

1,0-

10.0

1.0-10.0

1.0-

10.0

0.1-

1,0

1.0-10.0

0.1-

1.0

0.01-0.1

Gray

chem I/

1.8

30.0

1.7

4.7

2.42

1.45

0.07

4.6

0.36

0.04

clay spec

1.0-10.0

10*+

1.0-10.0

1.0-10.0

1.0-10.0

1,0-

10.0

0.1-1.0

1.0-10.0

0.1-

1.0

0.01-0.1

0\

I/ Chemical results =

oxid

es r

educed to

elements

Tabl

e 6.

Comparison

of ch

emic

al and s

pect

rogr

aphi

c analyses of

sam

ples

of I

daho p

hosphate ro

ck

(TWS

-124

, Lot

1202

; TW

S-12

5, Lo

t 1204;

TWS-

126,

Lot

1205

; TWS-12

?, Lot

1206)

Element

Si Cr V Ti P Mn Ca

Mg Fe Al

Lab. Ho.

35532

S. No.

RAE-47-10

chem I/

spec

7.06

0.11

0.09

0.09

H.5

0.04

26.6

0.20

0.70

1.1*6

1,0-

10.0

0.1-1.0

0.1-

1.0

0.01-0.1

1.0-

10.0

0.001-0.01

10.+

0.1-

1-0

1.0-

10.0

1.0-

10.0

350-59

ME-47-46

chem

I/

spec

8.28

0.13

0.04

0.11

12.2

0.03

29 »o

0.22

0.55

1,44

1.0-10.0

0.1-

1.0

0,01

-0.1

0,01-0.1

10.+

0.001-0.01

10.+

0.1-

1.0

0.1-

1.0

1.0-

10.0

35^6

3 LE8-47-36

chem

I/

spec

2,21

0.07

0.01

0,02

15.3

0.01

35.0

0.15

0,44

0.42

1,0-10.0

0.1-1.0

0.01-0.1

0.01-0.1

10.+

0*00

1-0.

01

10.+

0.1-1.0

1.0-10.0

1.0-

10.0

3559

4VEM-47-253

chem

I/

spec

4,10

0.11

0.02

0.04

10.4

0.06

32.3

0.55

0.49

0.75

1.0-10J

0.1-1.0

o.oi

-o,:

0,01

-0.:

1.0-

10.C

o.oi-o^:

10,+

0.1-

1.0

0.1-1.0

1.0-

10J

Chemical results

= ox

ides

re

duce

d to

elements

Table

7* Compa

riso

n of chemical and s

pectr©graphic

anal

yses

of

Colorado Plateau uranium-

and vanadium-bearing o

res

for

lead

(TWS-175,

Lot

0-21)

Sample no

.

LRS-

6-48

IBS-7-W

LRS-21-48

LRS-22-48

LRS-26-48

LRS-32-48

LRS-

33B-

48

LRS-

34-4

8

LRS-

35A-

48

LRS-39A-48

LRS-

43-^

8

LRS-

6o-i

i-8

LRS-

67-^

LKS-

69-4

8

(Percent P

b)

chem I/

0.10

0.16

0,11

0.00

3

0.013

0.00^

0.010

0.22

0.004

0.10

0,12

0.0^5

0.11

0.011

(Per

cent

Pb)

sp

ec

0.1-

1.0

0.1-

1,0

0,1-

1.0

0.1-1,0

0.01-0.1

0.01

-0,1

0,01

-0.1

0,1-

1.0

0.01

-0.1

0.1-

1.0

0.1-

1.0

0.01-0

.1

0.1-

1.0

0.01

-0.1

I/ Chemical results =

oxid

es re

duced to

el

ements

Tabl

e 8,--Comparison o

f chemical a

nd spectrographlc analyses of

mis

cellaneous sa

mple

s

Elem

ent

Mg Al K V Fe Si Ca Mn U Sr Ba

Montro

seit

e I/

chem

6/

spec

51.7

10.+

6.8

1.0-10.0

Humm

erite

2/

chem 6/

spec

5.5

1.0-10.0

0.10

0.

1-1.

0

3,6

1.0-

10.0

37.4

10.+

Oo31

0.1-1.0

0.03

0.01-0.1

Ore

3/

chem 6

/ spec

0.05

4 0.

1-1.

0

10.9

1.0-

10.0

0.007

0.01

-0.1

0.01

4 0.01-0.1

3.88

1.0-10.0

47.5

10.+

0,072

0.1-

1.0

0.25

0.1-1.0

Idoc

rase

4/

chem 6

/ spec

3,3

1.0-

10,0

17.3

io.+

24.4

10

.+

0.047

o.oi-o a

He-^ettite 5/

chem 6/

spec

0..96

0, 1-1,0

0.07

0.

1-1.0

45.9

io.+

0.23

0*1-1.0

20

APPENDIX 1

Composition of standard solutions

The following standard solutions were made from compounds and

elements available in the laboratory. Many of the compounds and

elements used were Johnson, Matthey and Co. "Speepure" grade (J and M),

The compounds were dissolved in distilled water unless otherwise noted,

Element Compound , _ standardized used Solution

Ag AgNOs, reagent

Al A1C13 '6H20,C,P. Compound dried in oven at 1*K) 0 C. anddissolved in cold acidified H20,

As As203 , lat. Bur. I;;! M03 , heated e Diluted to volume St. Ho. 8^a with H20.

B HsB03 , C.P.

Ba BaCl2 *2H20,C*P.

Be Be, metal, Dilute HC1. J and M

Bi Bi, metal, 1?1 M03 . Diluted to volume with H^. J and M

Ca CaCl2 *2H20, anal. reag.

Cb Cb, metal, k& percent HF. Diluted to volume with J and M HHO-s, cone.

CdC.P.

Ce Ce02 , J and M H2S04, cone., heated to form amber, Ce(S04 ) 2 .6 percent H2SOs added to form en.lGi-less Ce2 (304)3 . Diluted to volume with H20.

21

Element standardized

Co

Cr

Cs

Cu

By

Er

Pe

Ga

Ge

Gd

Hf

Hg

In

K

La

Li

Mg

Compound used

CoCl2 '6H20,C.P.

K2Cr207 , C.P,

CsCl, C,P*

CuO, reagent

By203 , J and M

Er203 , J and M

Pe, metal, J and M

Ga, metal, C^P.

Ge02 , C,P.

Gd203 , J and M

Hf02, J and M

HgCl2 , reagent

In, metal, J and M

HKCe&iCU, Hat. Bur. Stand,

La203 , J and M

Li2C03 , reagent

Mgj metal, J and M

Solution

Dilute HC1.

Isl HC1. Diluted to volume with E20.

1:1 HClc Diluted to volume with H20.

Dilute E2S04 -

Aqua regia. Diluted to volume with H20.

HF, k& percent. E2S04 , cone., added and heated to drive off HF. Diluted to volume with EsP*

Dilute EC1.

Dilute H2S04 , heated, and E202, 3 percent, added until dissolved. Diluted to volume with E20,

EN03 , cone. Diluted to volume with E20.

Dilute HC1.

Dilute HC1,

Dilute HC1,

Mn MnCl2

22

Element standardized

Mo

Na

Wd

Ni

P

Pb

Pr

Pt

Rb

Re

Sb

Sc

Si

Sm

Sn

Sr

Ta

Compound used

Mo, metal, J and M

EfaCl, reagent

Hd203 , J and M

Ni, metal, J and M

NaH2P04 *H20 C.P.

Fb(H03 ) 2 , C 0 P.

P-^sOn, J and M

Pt, sheet

RbCl, J and M

Re, metal, J and M

SbI3 , C.P.

Sc2 (S04 )3 -5H20, J and M

Si02, pure

Sm203 , J and M

SnCl2 -2H20, reagent

SrCOs, reagent

Ta, metal, J and M

Solution

Acjua regia, heated. Diluted to volume with EjpO.

1:1 HC1. Diluted to volume with H20.

1:1 HN03 , heated. Diluted to volume with H20*

1:1 HC1. Diluted to volume with H20.

Aqua regia. Boiled down several times with HC1, cone., to drive off HN03 » Diluted to volume with H20.

HN03 , cone. Diluted to volume with E2Q.

Acetone + HC1, dil.

Na2C03 fusion. Diluted to volume with H20

Dilute HC1.

Dilute HC1.

k-Q percent HF + M03 , cone. Diluted to volume with H20.

Element Compound standardized used Solution

Th

Ti

Tl

U

V

¥

Zn

Zr

C,,P,

Ti02 , C.P.

C.P.

(U02 )(C2H302 )2 2H20, C.Po

3; C.P.

¥,, metal;

"203 ^ J and M

ZnO^ reagent

ZrOCl2 *8H20,C.P.

48 percent HF + H202 . E2S04 , conc tt , added and heated to drive off HP, Diluted to volume with H20.

Hot H20,

48 percent HF 4- EN03 ^ cone., heat. Diluted to volume with H20.

1:1 HC1 and heat. Diluted to volume with H20c

Dilute HC1.